Prozac in Drinking Water? Likely So
Water Treatment Plants Not Designed to Get Rid of Medications
WebMD News Archive
August 10, 2004 -- Scientists in Great Britain have found levels of a common antidepressant in the water. It begs the question: What about the drinking water in the U.S.? Should we be concerned?
The exact quantity of the antidepressant Prozac -- found in river systems and groundwater used for drinking -- was not specified. However, the British report says that it could be potentially toxic.
Similar problems have been discovered both with prescription and nonprescription drugs in the U.S. and throughout Europe, albeit at low levels. Many have questioned whether even low levels of these medications could affect human health and reproduction.
The First Report
In 2002, the U.S. Geological Survey (USGS) released the first study of pharmaceuticals, hormones, and other organic wastewater-related chemicals in streams across the nation. Most sites were downstream of urban and farming areas where wastewater is known or suspected to enter streams.
The study showed that:
- Pharmaceuticals, hormones, and other organic wastewater-related chemicals have been detected at very low concentrations in streams across the U.S.
- Many of the chemicals examined (81 of 95) do not have drinking-water standards or health advisories. Measured concentrations of compounds that do have standards or criteria rarely exceeded any of them.
- Among the chemicals detected were: human and veterinary drugs (including antibiotics), natural and synthetic hormones, detergents, plasticizers, insecticides, and fire retardants.
- Some of the compounds most frequently detected include: coprostanol (a fecal steroid), N-N-diethyltoluamide (an insect repellant), caffeine, triclosan (an antimicrobial disinfectant), tri (2-chloroethyl) phosphate (a fire retardant), and 4-nonylphenol (a detergent by-product).
- 38 chemicals were found in a single water sample.
This week, an update on that report will be released, says Herb Buxton, coordinator of the United States Geological Survey's Toxic Substances Hydrology Program.
The news is not good: "The compounds we use in small amounts can get significantly concentrated because of how we handle wastewater," Buxton tells WebMD. "Our filtration systems aren't built to treat these kinds of chemicals -- organic chemicals. We need more sophisticated technology to filter them."
Most problematic, Buxton says, is whether antibiotics in the environment cause antibiotic resistance. Also, could natural human hormones as well as synthetic hormones (birth control pills, hormone supplements, and estrogen-like compounds such as detergents) affect fertility?
His data will be used by the American Waterworks Association, the EPA, the FDA, and other agencies to address those questions.
What's Being Done?
The main problem is outdated water treatment systems. "There are a bunch of systems out there, they are probably effective to some degree, but they're probably not completely effective," says Ephraim King, JD, director of standards and risk management in the EPA's Office of Water.
"Each city, each town has some kind of treatment system in place," he tells WebMD. "But that system will vary according to the contaminants they're trying to address, and the system's age. ... The filtering systems may not be capable of removing certain chemicals like pharmaceuticals."